In U.S. patent application having Ser. No. 104,375 filed Dec. 17, 1979 by Mr. Robert L. Wallace, Jr., and assigned to the same assignee herein, and now U.S. Pat. No. 4,311,874 there are disclosed acoustic arrays, each comprising a plurality of discrete transducers. The discrete transducers are located with precision according to a predetermined relationship in order to produce a response pattern with preselected directional characteristics.